Method of attaching opener keys to end closures of tear strip cans



Dec. 30, 1941. F. J. O'BRIEN 9 9 METHOD OF ATTACHING OPENER KEYS TO END CLOSURES OF T EAR STRIP CANS Filed Aug. 15, 1940 IVENTOR.

A T TORNE Y5,

Patented Dec. 30, 1941 METHOD OF ATTACHING OPENER KEYS TO END CLOSURES OF TEAR STRIP CANS Frank J. O'Brien, Pelham, N. Y., assignor to Continental Can Company, Inc., New York, N. Y., a corporation of New York Application August 13, 1940, Serial No. 352,444

2 Claims.

The invention relates generally to metallic receptacles of the well known tear strip type which are opened by tear strip winding keys removed from temporary attachment to the receptacles which they are meant to open, and it primarily seeks to provide a novel method of effecting the temporary attachment of said keys by welding.

Tear strip winding keys have been attached to metallic receptacles in various ways prior to the present invention, as by soldering, and even by welding, but these methods of attaching the keys have presented certain problems and diflicultles. An example of these difficulties is the necessity of providing a weakened or break portion in the shank or body of the key well back of the point of attachment, necessitating separate operations and the use of additional metal. Unless such weakened portions are provided, keys welded to receptacles have been known to pull away metal portions of the receptacles at the points of Weldattachment during removal of the keys from their temporary attachment.

It is, therefore, an object of the present invention to provide a novel method of attaching a tear strip winding key to a metallic receptacle by welding and consisting in placing the key with its shank or body portion overlying the receptacle portion to which it is to be temporarily attached, and applying a welding electrode thereto with sufficient pressure to efiect the desired weld-attachment and simultaneously re- 'duce the thickness of the shank or body portion directly at the weld attachment thereby to enable subsequent removal of the key by breakage of said thinned and weakened portion without danger of pulling away of metallic receptacle portions to which said key had been attached.

Another object of the invention is to provide a novel method of the character stated in which the electrode mentioned is pressed against a porthe key is made to a central portion of an ,end

closure for a can body. It is to be understood, however, that the invention comprehends the attachment of tear strip winding keys to any portion of a metallic receptacle.

In the drawing, 5' designates an end closure which may be shaped in the conventional manner to include a heel or annular wall portion 6 adapted to snugly fit within a flanged end of a can body and which is surrounded by the usual outwardly directed flange 1 adapted to be seamsecured to the flanged end of said can body. See.

Fig. 1.

The end closure 5 is preferably, but not necessarily, provided with a centrally disposed raised hump 8 for facilitating attachment of the tear strip winding key in accordance with the present invention.

The key includes the usual gripping head or handle 9 and a body or shank portion l0 which may be partially flattened in the usual manner and slotted as at H to receive the tear strip which is to be wound by the key.

In practicing the improved method of attaching tear strip winding keys, the end closure portion including the central hump 8 is preferably supported over an anvil i 2 which may be an electrode, depending upon the type of welding which is employed in effecting the attachment. See Fig. 2. With the end closure thus supported and the key positioned with the end extremity of the shank or body portion ll contacting the hump 8, a welding electrode I3 is pressed against said end extremity, preferably over a limited width only at said end extremity so as to simultaneously apply heat and pressure sufficient to weld the key extremity to the end closure hump 8 and spread and thin out the contacted limited area of said extremity as at 14. See Figs. 3 and 4. By thus thinning the key shank extremity, or rather the limited portion thereof, a proper weld-attachment or the key is effected, and a subsequent removal of the key thus attached can be effected by merely gripping the key head 9 and lifting the same so as to impose a bending strain on the thinned and weld-attached portion ll suflicient to r apture the same. See Fig. 5. Because of the thinning of the portion H as an incident to the weld-attachment thereof, this rupture can be eflected without any danger of pulling away any portion of the metallic receptacle during the removal of the key from its temporary attachment with said receptacle.

As previously stated, it is preferred that the weld-attachment be made in the particular manner illustrated to an end closure of a metallic receptacle, but it is to be understood that this attachment can be made to other portions of me-,

tallic receptacles if desired.

I claim: A

l. The method of securing a metal tear strip winding key to a metallic receptacle part comprising positioning the key with the free end of the shank in contact with the receptacle part, supporting the receptacle part, applying a welding electrode to the end extremity of the shank so as to partially overlie the end thereof and establishing an electric welding current circuit through the electrode, the key shank and the receptacle part, and simultaneously moving the electrode relative to the support with suflicient pressure to deform the shank end extremity and weld the key to the receptacle part without any substantial thinning of said receptacle part and to render the key shank so thin where it is joined to the weld that separation of the key from the receptacle part may be easily accomplished by a rupturing of the metal joining the key shank to the weld.

2. The method of securing a metal tear strip winding key to a metallic receptacle part comprising positioning the key with the free end of the shank in contact with the receptacle part, supporting the receptacle part on a relatively large electrode, applying a relatively small welding electrode to the end extremity of the shank so as to partially overlie the end and establishing an electric welding current circuit through said electrodes, the shank end extremity and the receptacle part thereby to generate heat sufllcient to weld-attach said shank and extremity and said receptacle part and simultaneously moving the electrodes relatively toward each other with sufiicient pressure to deform the shank end extremity and weld the key to the receptacle part without any substantial thinning of said re- I ceptacle part and to render the key shank so thin where it is joined to the weld that separa- 1 tion of the key from the receptacle part may be easily accomplished by a rupturing or the metal joining the key shank to the weld.

' FRANK J. OBRIEN. 

